I've never understood how to answer this type of problem. Your explanation of the equal and opposite force acting on the disk was the key... thanks very much!
For Impulse Momentum priniciple,it is the change in force or the net force in the system is equal to change in momentum right. why did you use F as the resultant force. The resultant force should be zero right since it is acting equal and opposite direction.
Why is the value of K not taken to 1 in Manning's equation, whereas it is taken as 0.849 (SI units) in the Hazen-Williams equation? Shouldn't K in Manning's equation also be expressed in SI units?
Why isn’t the answer the sum of forces divided by two so 4.5kN for just the plate. Is it because the equation is for the resultant force? Thank you for these videos they are of great help to me and my wife
Hi Eduard, so the goal here is to solve for the reaction force "F" on top of the plate. The principle of conservation of momentum is applied here where the right side of the equation used above accounts for the forces due to kinetic energy. After finding the value on the right side we know this is the "upward force action" applied to the plate therefore we have to have an equal and opposite "downward force reaction" which will be our "F".
The minus sign should still be there. It will give us a negative value for the force which at the end tells us the reactionary force the plate responds with is acting down.
